High-voltage power supply The high-voltage power supply (HVPS) applies biases to the following components: ● Primary charging roller ● Developing roller ● Transfer roller Figure 1-11 High-voltage power supply Engine controller 18 Chapter 1 Theory of operation ENWW DC controller High-voltage power supply Primary charging bias circuit Developing bias circuit Transfer bias circuit To primary charging roller To developing roller Cartridge Photosensitive drum Transfer roller